MMET 207 EXAM 2 - TAMU – CRAIG
Cold work - answers :o, w, a, d
O series (cold work) - answers :oil hardening
O1, o2, o6, o7
W series (cold work) - answers :water hardening
W1, w2, w5
A series (cold work) - answers :medium alloy air hardening
A2, a4, a6, a8, a9, a10, a11
D series (cold work) - answers :high carbon, high chromium
D2, d3, d4, d5, d7
Shock resisting - answers :s series
S1, s2, s4, s5, s6, s7
Hot work - answers :h, p
H series (hot work) - answers :h10-h19 chromium types
H20-h39 tungsten types
H40-h59 molybdenum types
P series (hot work) - answers :molded
P6, p20, p21
High speed - answers :m, t
M series (high speed) - answers :molybdenum types
M1, m2, m3-1, m3-2, m4, m6, m7, m10, m33, m36, m41, m46, m50
T series (high speed) - answers :tungsten types
T1, t4, t5, t6, t8, t15
Special purpose - answers :l series
L2, l6
Carbon steel hardening properties - answers :hardenability: biggest back curve/worst
hardenability
Hardness: sharp drop as temper temp increases
Abrasion resistance: wear volume grows the most over time
Alloy steel hardening properties - answers :hardenability: middle largest back
curve/middle hardenability
, Hardness: slow decline
Abrasion resistance: medium wear volume amount
Tool steels - answers :hardenability: smallest back curve/best hardenability
Hardness: goes down a little, then back up, then sharp drop
Abrasion resistance: least amount of wear volume
Safety in hardening - answers :risk of damaging from hardneing (quench cracks)
Eutectic structures - answers :spread out carbide structures
Eutectic networks - answers :long multiple chains of carbide structures
Severe banding (cause and effect) - answers :-caused by segregation of the alloying
elements during solidification
-causes anisotropy in the tensile ductility and impact energy of the steels
Why are eutectic material and severe banding undesirable? - answers :makes the tool
steel crack easier
Hardening characteristics (4) - answers :safety in hardening
Depth of hardening
Size change in hardening
Resistance to decarburization
What is secondary hardening? - answers :the unintentional increase of hardness during
tempering or machining of some hardened high alloy steel
Depth of hardening - answers :through hardening, hardenability
Size change in hardening - answers :very important for design
What is decarburization - answers :if a steel with a relatively high carbon content (~1%)
is heated in a furnace that has a carbon-free atmosphere (air), carbon will tend to
diffuse out of the steel
Hardening- use characteristics - answers :resistance to heat softening
Wear resistance
Toughness
Machinability
Resistance to heat softening - answers :the capability of an alloy to maintain its strength
when exposed to high temperature
Wear resistance - answers :a material's ability to resist material loss by some
mechanical action
Cold work - answers :o, w, a, d
O series (cold work) - answers :oil hardening
O1, o2, o6, o7
W series (cold work) - answers :water hardening
W1, w2, w5
A series (cold work) - answers :medium alloy air hardening
A2, a4, a6, a8, a9, a10, a11
D series (cold work) - answers :high carbon, high chromium
D2, d3, d4, d5, d7
Shock resisting - answers :s series
S1, s2, s4, s5, s6, s7
Hot work - answers :h, p
H series (hot work) - answers :h10-h19 chromium types
H20-h39 tungsten types
H40-h59 molybdenum types
P series (hot work) - answers :molded
P6, p20, p21
High speed - answers :m, t
M series (high speed) - answers :molybdenum types
M1, m2, m3-1, m3-2, m4, m6, m7, m10, m33, m36, m41, m46, m50
T series (high speed) - answers :tungsten types
T1, t4, t5, t6, t8, t15
Special purpose - answers :l series
L2, l6
Carbon steel hardening properties - answers :hardenability: biggest back curve/worst
hardenability
Hardness: sharp drop as temper temp increases
Abrasion resistance: wear volume grows the most over time
Alloy steel hardening properties - answers :hardenability: middle largest back
curve/middle hardenability
, Hardness: slow decline
Abrasion resistance: medium wear volume amount
Tool steels - answers :hardenability: smallest back curve/best hardenability
Hardness: goes down a little, then back up, then sharp drop
Abrasion resistance: least amount of wear volume
Safety in hardening - answers :risk of damaging from hardneing (quench cracks)
Eutectic structures - answers :spread out carbide structures
Eutectic networks - answers :long multiple chains of carbide structures
Severe banding (cause and effect) - answers :-caused by segregation of the alloying
elements during solidification
-causes anisotropy in the tensile ductility and impact energy of the steels
Why are eutectic material and severe banding undesirable? - answers :makes the tool
steel crack easier
Hardening characteristics (4) - answers :safety in hardening
Depth of hardening
Size change in hardening
Resistance to decarburization
What is secondary hardening? - answers :the unintentional increase of hardness during
tempering or machining of some hardened high alloy steel
Depth of hardening - answers :through hardening, hardenability
Size change in hardening - answers :very important for design
What is decarburization - answers :if a steel with a relatively high carbon content (~1%)
is heated in a furnace that has a carbon-free atmosphere (air), carbon will tend to
diffuse out of the steel
Hardening- use characteristics - answers :resistance to heat softening
Wear resistance
Toughness
Machinability
Resistance to heat softening - answers :the capability of an alloy to maintain its strength
when exposed to high temperature
Wear resistance - answers :a material's ability to resist material loss by some
mechanical action
